Propeller.



J. R. LISTON.

PROPELLER.

APPLICATION FILED 0(1T.25, 1910 Patented July 2, 1912 2 SHEBTSSHEET l.

ATTORNEY WITNESSES J. R. LISTON.

FROPELLER.

APPLICATION 00'1" 1910,

Patented July 1912 2 SHEETS-SHEET 2,

WITNESSES ATTORN EY .Y ciently light construction JAMES'B. LISTON, 0F PACIFI BEACH, CALIFORNIA.

PROPELLER.

To 'all whom it may concern:

Be it known that I, JAi-irias R. LISTON, acitizen oft-he United Shites,r esiding at Pa cifie Beach, in thecount-y of, San Diego and State of California; have invented a new and useful Propeller, of which the following is a specification.

This invention has referenceto improve iiients in propellers, and its object is to prowhich shall be of Spillto be itilizable in connection withJair ships, but at.the same vide a propeller *time shall besufliciently rigid to resist the sti ains'putther'eon in service. Furthermore,

' rigidity of the propeller whatever be the use. to, which it isput'.

the propeller .blades maybe-shaped as'Qdes ired, or-their shapechaiiged frontfiii e to time without in any manner affecting the In accordance with the present invention the propeller blades are made of some lig it sheet metal such, for instance, as aluniiniim, although other metals may be used, and these propeller blades are backed up by spring metal arms, such, for instance. as

spring steel, -and straining .rods are carried fromthese arms. through the propeller blades to suitable connections with the propeller shaft, SOlllat by adjustments of the straining rods the shape of the propeller blades may be readily changed as found expedient, such changes being facilitated by the tendency of the propeller blades to return to a poi-mail condition due to the spring metal arms fast to such propeller blades.

The invent-ion i\'ill be best understood from a consideration of the following dctailed description taken in connection with the accompanying drawings forming a part of this specification, with the understanding.

- however, that the showing of the drawings iii largely indicative without attempt to ili strate relative proportions, 'and, therefore, it follows that various changes and modifications may be made in the practical embodiment of the invention without departure from the scope ofthe invention, and

, -while still retaining the salient features thereof.

In the drawings:- Figure 1 is an elevation of'a propeller constructed in accordance with the present invention looking at the active facet-hereof. l ig. 21s an elevation of the other face of the propeller with the propeller shaft in section. Fig. 3 is a side elevation of the propeller as viewed from the Specification of Letters Patent.

Application filed October 25, 1910. Serial No. 589,075.

Patented July 2, 1912.-

l ft hand side of Fig. 191m 4 is a fIOIl .on the line 4-4 of Fig. 3 drawnto a larger scale and omit-ting some of the parts.

blades; Fig. 6 is an edge view thereof. Fig.

tionwith the propeller. j

a propeller shaft 1 which may be of'ordina ry construction, and in the ease of an air ship 18 usually the crank shaft or a continuaengine is reduced in diameter to form a stem 2 to which is applied the sleeve 3,'terminating at the end remote from the shaft in a .radial flange 4, and f-matching. ths'fiange 6 which, when the parts, are assembled, is in alinenient with the sleeve 3. The stem 2 but there is provi ed a continuing member in the form of a sleeve 7 on a rod 8 having one end9 threaded'and inserted in the reduced end 2 of the shaft 1, so that the sleeve 7 and rodS are in effect part of the shaft 1. The flanges 4- and 5 receive'between them propeller blades 10, each of which, as indicated in the drau-ings, has a comparatively narrow neck end 11 extending between the able rivets 12, or by any other suitable fasteiilng means, and from these neck ends the blades expand in width and curve iii the direction of rotation of the propeller. The blades are, also, given a "partial twist and pitch which may be varied within comparatively \vide limits. so that the blades are adapted to varying conditions of use. Fast to the flanges 4 are arms 13, 14, rivets 15 or' other fastening means being employed for securing these arms to the flange, and where the rivets'coincide with the blades they may be utilized as a further fastening means for'the blades. These arms 13 and 1+ extend from the flange 4 and together conform to a material portion of the marginal part of each fan blade, there being an arm 13 and an arm 1 for each blade. The arm 13 extends along and conforms to theitor other suitable fastening means.

see-.-

Fig. 5 is a face view of one of the propeller- 7 is .aperspective of a link used in connec- Referring to the drawings, there is shown tion of the'crank shaft of an explosion en-' gine. Thleend of the shaft remote from the These 7 arms are secured to the fan blades by rivets 1101 The fan blades are made of sheet metal- 4 is another like flange 5 formed of a sleeve of the shaft 1 sto 5 short of the flange 4,

flanges 4 and 5 and there secured by sult-' and because of the construction may be quite thin and light, sheet aluminum answering for fan blades of large diameter when'designed for use in connection with air ships,

the arms 13 and 14'for each blade imparting sufficient rigidity to cause thin metal blades to withstand .the strains put upon them in use. The arms 13 and 14 are made of spring metal, such as spring steel and tend constantly to assume a predetermined position, either that in which the blades are flat or in one plane, or in which the blades have a minimum degree of pitch.

The rod 8 extends beyond the sleeve 7 in a direction away'from the fan blades, and

athero receives an appropi iate number of links 17, each formed at one end into an eye 18 through which the rod 8 is passed, and at the other end into an angle extension 19 through which there is a perforation, so that the angle extension 19 is also an eye. Each arm 13 and 14 is providediwith perforations appropriately spaced, the arm 14 havingusually two such perforations'and the arm 13 one perforation, and the corresponding blades are similarlyperforated to match the perforations in the arms. Ex-

tending. through these several perforations for each blade.

are straining rods 20, 21, 22 in the particular construction shown in the drawings,

' :rods'iieing so spaced as to include the for- *ward end of the blade, these two rods extending through the arm 14 near its outer end and near the end where the arm passes from .the blade toward the flange 4, it will be understood that in large fans more rods may be necessary, so that the invention is not confined to any specific number of strain- 0 ing rods.

The sleeves 3 and 6 are held against the shoulder on the shaft 1 formed by the reduced end 2 by means of a collar 25 secured to a set screw 26, but this does not preclude the direct fastening of the sleeves 3 and 4 to the shaft and tothe sleeve 7, respectively.

The outer end of the rod 8 is threaded forthe reception of a nut- 27 which while pre senting a preferable construction, is not mandatory.

The links 17 and the propeller hub formed by the sleeves 3 and (l with the respective flanges/i and 5 are in substantially fixed re lalion one to the other. Now by an appropriate manipulation of the nuts 24 an y desired pitch of the fan blades may be impart.

' mal tendenc ed thereto, since a screwing of the nuts on the rods will tend to draw the outer edge of each fan blade in a direction toward the links 17, thus bending the arms 13 and 14 to a commensurate extent against their norand imparting a curve or pitch to the lades corresponding to the de ree of shortening of the effective length of. t 1e rods. blades are fast to the hub of the fan, the clian ing in the length of the strainin rods is e ective on the outer edge of eac fan blade, and since the points of action of the rods on the fan blades are distributed, these blades are readily giventhe desired curvature, 'the elasticity of the arms 13 and 14 aiding materially i'n impartinga regularity of curvature to the portions of the blades acted upon.

Because of the straining rods and the clastic, arms, 13 and 14, which latter may he made of great strength compared to their weight, the thin metal blades are so reinforced that they will withsta'nd with an ample margin of safety all the stresses and strains put upon them under actual working conditions, as 'has 'been demonstrated by practical tests on propellers of large diameter when rotated at high speed for air ship pro ul'sion.

, en the propeller is active, the strain is brought upon those faces of the blades.to-

wa -d the links 17 and these strains are wit stood by the straining rods, these rods being so distributed-"as to sustain the blades over practically the entire free edges thereof, and since the strains are in substantially the direction of the length of the rods, the

latter may be made quite light without dangerof rupture, so'as to present but little resistance surface to the air, assuming the propeller to. be used for air ship propulsion. Torsional strains are taken care of by the arm's'13 and 14, and these arms may be made of ample strength for the purpose without undue weight.

- -'[he propeller is of general circular form with the blades each of general spiral shape, widening toward the outer or advanced ends, and the shape is such asto bring the pressure of either air or water, in accordance with the use to which the propeller is put, to bear upon the body of the blades in such manner that the arms 13 and 14 and the stay rods connected thereto will effectually resist suchpressurc. Because of the shape of the blades they may be expanded without proportionately increasing the radial distance of the outer edges of the blade from the axis of rotation and the width of the blades may also be increased, so that the oll'ect of the propeller may thereby be greatly augmented without necessitating a corrcspondlng Increase Ill (.llamctcr;

The construction of the propeller con- Since the inner ends of the fan tributes toward making the same a balance wheel, the entire propeller being a balanced structure, and may, therefore, be attached directly to the engineshaft.

What is claimed is 1. A propeller provided with a suitable hub, sheet metal blades each fast at one end to the hub and extending therefrom with a curvature in the direction of rotation and also widening in the same direction, brace arms for each blade one extending along and conforming to the trailing portion of the blade and the other extending along and conforming to the leading portion of the blade and each at one end secured to the hub, and a plurality of straining rods each connected at one end to abrace arm.

2. A propeller comprising a hub, blades each fast at one end to the hub and extending therefrom with a curvature in the direction of rotation and also widening in the same direction, brace arms each connected at one .end to the hub, there being provided a brace arm for each blade fast to said blade along the trailing portion of the blade and another brace arm fast to the blade along the leading portion thereof, and stay rods for each blade engaging the brace arms.

3. A propeller comprising a hub, sheet metal blades each fixed to the hub at one end, elastic reinforcements extending from the hub along the margins of each blade, and a plurality of stay rods for each blade adjustable with relation thereto in opposition to the normal tendency of the elastic reinforcements.

4. A propeller comprising a hub portion,

thereof, and stay rods for each blade engaging the elastic arms and adjustable to bend the blades in opposition to the normal tend envy of the elastic arms. I

5. A propeller comprising a shaft, a suitable'hub thereon, sheet metal. blades each fast at one end to the hub, a plurality of elastic arms for each blade fast to the hub and to the blade near the margin thereof, a plurality of stay rods engagingthe elastic arms of each blade and in adjustable relation to the shaft,

A propeller provided with a suitable shaft, a hub mounted on said shaft, sheet metal blades each fast at one end to the hub and extending thcrefrom with a curvature in the direction of rotation and also widening in the same direction, elastic brace arms extending from the hub along the margins of each blade, a plurality of straining rods each connected at one end to a respective el astic brace arm, and a link individual to each rod and connected to the shaft, the rod be ing provided with means for varying its effective lengthto determine the curvature of the respective blade.

In testimony that I claim the foregoing as my own, I have hereto atiixed my signature in the presence of two witnesses.

JAMES R. LISTON.

\Vitnesscs:

E. E. l-IUBBELL, VERA JUDKINS. 

